Matheson Tri-Gas Norfolk ASU

NPDES permit NE0139483 · Minor NON-POTW · effective, expires 2028-09-30 · EPA's file as of 2026-09-19

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EPA's record, 2025-09-01 to 2026-08-31

3values over a limit
0required values missing, on 0 form(s)
3of 10 forms filed late

Last period with anything received: 2026-06-30. Most often over: Chlorine, total residual (3).

Reporting

Reports are due about 89 days after each monitoring period ends (read off this permit's own late-day counts in EPA's filings).

Limits in force (36)

OutfallParameterStatisticLimitMonths
001Temperature, water deg. fahrenheitMO AVG report only all year
001Temperature, water deg. fahrenheitDAILY MX <= 90 deg F all year
001pHDAILY MN >= 6.5 SU all year
001pHDAILY MX <= 9 SU all year
001Iron, dissolved [as Fe]MO AVG <= 14.894 mg/L Jun, Jul, Aug, Sep, Oct
001Iron, dissolved [as Fe]MO AVG <= 20.941 mg/L Mar, Apr, May
001Iron, dissolved [as Fe]MO AVG <= 23.5 mg/L Jan, Feb, Nov, Dec
001Iron, dissolved [as Fe]DAILY MX <= 29.879 mg/L Jun, Jul, Aug, Sep, Oct
001Iron, dissolved [as Fe]DAILY MX <= 42.021 mg/L Mar, Apr, May
001Iron, dissolved [as Fe]DAILY MX <= 47.1 mg/L Jan, Feb, Nov, Dec
001Iron, dissolved [as Fe]MO AVG <= 2.19 kg/d Jun, Jul, Aug, Sep, Oct
001Iron, dissolved [as Fe]MO AVG <= 3.07 kg/d Mar, Apr, May
001Iron, dissolved [as Fe]MO AVG <= 2.08 kg/d Jan, Feb, Nov, Dec
001Iron, dissolved [as Fe]DAILY MX <= 4.39 kg/d Jun, Jul, Aug, Sep, Oct
001Iron, dissolved [as Fe]DAILY MX <= 6.17 kg/d Mar, Apr, May
001Iron, dissolved [as Fe]DAILY MX <= 4.16 kg/d Jan, Feb, Nov, Dec
001Manganese, dissolved [as Mn]MO AVG <= 23.5 mg/L Jan, Feb, Nov, Dec
001Manganese, dissolved [as Mn]MO AVG <= 14.894 mg/L Jun, Jul, Aug, Sep, Oct
001Manganese, dissolved [as Mn]MO AVG <= 20.941 mg/L Mar, Apr, May
001Manganese, dissolved [as Mn]DAILY MX <= 47.1 mg/L Jan, Feb, Nov, Dec
001Manganese, dissolved [as Mn]DAILY MX <= 29.879 mg/L Jun, Jul, Aug, Sep, Oct
001Manganese, dissolved [as Mn]DAILY MX <= 42.012 mg/L Mar, Apr, May
001Manganese, dissolved [as Mn]MO AVG <= 2.08 kg/d Jan, Feb, Nov, Dec
001Manganese, dissolved [as Mn]MO AVG <= 2.19 kg/d Jun, Jul, Aug, Sep, Oct
001Manganese, dissolved [as Mn]MO AVG <= 3.07 kg/d Mar, Apr, May
001Manganese, dissolved [as Mn]DAILY MX <= 4.16 kg/d Jan, Feb, Nov, Dec
001Manganese, dissolved [as Mn]DAILY MX <= 4.39 kg/d Jun, Jul, Aug, Sep, Oct
001Manganese, dissolved [as Mn]DAILY MX <= 6.17 kg/d Mar, Apr, May
001Flow, in conduit or thru treatment plantMO AVG report only all year
001Flow, in conduit or thru treatment plantDAILY MX report only all year
001Chlorine, total residualMO AVG <= .021 mg/L Mar, Apr, May
001Chlorine, total residualMO AVG <= .018 mg/L Jun, Jul, Aug, Sep, Oct
001Chlorine, total residualMO AVG <= .023 mg/L Jan, Feb, Nov, Dec
001Chlorine, total residualDAILY MX <= .042 mg/L Mar, Apr, May
001Chlorine, total residualDAILY MX <= .035 mg/L Jun, Jul, Aug, Sep, Oct
001Chlorine, total residualDAILY MX <= .045 mg/L Jan, Feb, Nov, Dec

Built from EPA's ECHO bulk files. EPA's file, not the permit document, is the source: read your permit. Check a report before you file it · All states